Welcome To The Family
by alienphantom
Summary: Well, brother, I think you'll see things my way soon enough." Ben shouted in distress as the creeping slime approached his elbow. "Welcome to the family" His Fusion said with a sinister grin.
1. Chapter 1

Chapter 1: Abduction

**Ka-THOOM!**

Ben leapt out of the way as a huge, clawed foot came down onto the ground where he had been standing. Green ooze dripped from the body of the Fusion monster as it thundered towards him on legs as thick as oak trunks. All around them, the sounds of battle echoed as the Earth's defense forces fought off another Fusion invasion of Downtown. The KND were the main force of troops until the new, volunteer soldier army could be trained and organized.

"Ha, you want a fight, slime-a-saurus? How about you pick on someone your own size?!" Ben taunted the towering creature that resembled a dinosaur built from an urban landscape held together by dark green slime. That was how Fuse operated; the slime infected whatever it could and made a working body from it, then recollected back into Planet Fuse when it was destroyed or no longer needed.

Ben tapped the controls on his Omnitrix and a green hologram shone from the face. After a few turns, Ben slammed down on the control dial and was engulfed in bright light that blinded the monstrosity intent on his destruction.

Ben felt the familiar sensation of his bones lengthening and thickening, his muscles bulging as his whole body was reshaped by inhuman DNA, transforming him to the core of his being. He pushed the transformation past its initial limit, growing to a size that equaled the Fusion monster before him.

_Humongosaur!_

"Bring it on, bub." The gravelly voice of his Vaxisaurian form rumbled. Ben pulled back a fist and slammed it into the side of the Junk-a-saurus attacking him, his great strength denting in its metal skull and nearly knocking its head clean off. However, it retaliated with a swipe of its tail, striking Ben in the knee and throwing him off balance.

Then, it rammed into him, attempting to throw him to the ground. Ben ground in his heels and kept his footing, bringing his immense fists down on the neck of the creature in front of him. There was a satisfying _crunch_ of metal and stone as whatever the Fusion used as a spine was cracked in half. Ben dug in his fingers and pulled, literally ripping the unnatural creature apart, spewing green Fusion Matter goo over the surrounding trees and buildings. The wielder of the Omnitrix frowned in disgust as he was splattered with chunky green slop.

"Okay, yeah, this crud makes Goop look like hand soap." Ben grumbled as he attempted to sling the repugnant, extremely foul-smelling sludge off himself, having only marginal success. He glanced down when the Omnitrix symbol, dwarfed by the sheer size of this form's massive chest, blinked green and made a beeping noise.

Ben reached up a hand and slapped it over the symbol, immersing him in a tornado of green energy. When the whirl of energy quieted, he stood in the place of Humongosaur as his normal self. He tapped a button on the side of his Omnitrix and spoke into it.

"Tennyson, here."

"Ben, where in Einstein's name have you been?" A child's voice colored with a Russian accent squawked from the alien device, courtesy of a secure communications line that the speaker had installed. Ben rolled his eyes at the angry tone.

"Chill, Dexter. I just had to put the beat down one butt-ugly monster. Humongosaur took him out pretty easily, though." The voice on the communications line was none other then Dexter, multi-billionaire, super genius head of Dexcorp and its main outlet, Dexlabs. He had invented most of the hyper-advanced technology that allowed the Earth to hold its own against Fuse. He had turned thirteen last September. And he did not sound happy.

"Well, since you're clearly safe enough to chat, I need you to head over the western front. Several Granite Grabbers are trying to dig beneath the defenses there, and both The Powerpuffs and Samurai Jack are busy elsewhere." Ben snapped a jaunty salute the boy genius couldn't see.

"Aye aye, General Genius."

'Wait, Ben, there have been sightings of Fu-" Dexter's voice was cut off as Ben slammed down on the Omnitrix and let the Galvan technology take him over, transforming him in a flash of light.

_Jetray!_

Ben spread his arms and took to the sky, jetting high above the ground in a few flaps. Using this form's excessive speed and agility, Ben took a shortcut through the skyscrapers of Downtown, zigzagging between buildings in a more-or-less straight path towards his destination.

Before he could reach his destination, he was hit in the back by a lance of dark green energy that made him screech in pain and veer off course, scraping the glass off a single floor of a building until he was able to right himself. He swiveled in mid-air and fired off neuroshock blasts from his eyes, but whatever was chasing him disappeared in a blur of green. He dashed off after the green blur as it jetted through the air, matching every attempt he made to catch it.

"Get back here and fight like a Fuse!" Ben challenged the fleeing shape, then fired an orb of green energy from his tail, which collided with the back of the green figure he was chasing.

It began to careen towards the ground, and landed with a muffled explosion and a burst of dust and debris in the middle of a large park. Ben streaked after it, changing back to his own body in a flash of green as he landed.

"Okay, you slimy son-of-a…huh?" The target Ben had been chasing was nowhere to be seen, simply a crater where it had landed. He glanced back and forth, but this part of town was deserted, since the infection has spread dangerously here. A few hundred feet away, Ben could a large statue of some heroic figure sinking into the toxic ooze. Around him, most of the plants had begun to wither and die, with only the largest, hardiest trees still retaining any sort of life. The stench was strong enough that it made him pinch his nose to combat the smell.

He was caught unawares by a strike to the back, strong enough to send him flying and crash into a boulder. The impact gyrated up his spine; vibrating his teeth and sending a shooting pain through his body from the wound between his shoulders.

Ben's attacker strode towards him, briefly silhouetted in a flash of green light. As the being stood in front of him, Ben gasped in shock.

"Oh, hell." Ben swore, when he got a look at his attacker, and was greeted by a vision from a nightmare. His familiar features, distorted and twisted by Fusion matter, gazed back at him. Dark green skin, glowing red eyes under a mop of matted, brown hair, and a reversal of his own clothing; a red jacket with black accents, a black undershirt and jeans, and red and black shoes. This twisted copy of one of Earth's greatest heroes was his Fusion, copies of Earth's defenders made to beat them with their own abilities.

"Hello, brother. My, you seem to be off your game today. Usually such an attack wouldn't have even hit you. Ah, such a shame." The Fusion taunted, a sadistic smirk curling under its nose.

Ben glared at his Fusion, unamused by the wit which reminded him so much of Albedo, the vengeful Galvan stuck in a copy of Ben's body.

"Yeah, well, I've got better things to worry about then some second rate copy. I've already got one, I don't need another." Ben shot back, leaning against the boulder behind him as he rose from the ground.

The Fusion shook it's head, seeming to find entertainment in Ben's reply.

"Oh, I present much more of a threat then our dear friend Albedo ever could. After all, I know everything about you. Perhaps I should drop by Bellwood, and swell our ranks by one more? Surely a face as pretty as your girlfriend's would look good in green?"

Ben glared at the copy of himself, anger coloring his features. Behind his back, his hand touched on the Omnitrix.

"I swear, if you so much as get within a _MILE_ of Julie, I will beat you into the green slime you really are!" Ben bellowed, while the Fusion before him smirked.

'Ah, but we're all alone here. What will you do about it, without any precious friends to back you up?" The Fusion questioned, sadistic pleasure making it bear its green-tinged teeth with a gruesome smile.

Ben was about to rely, but was cut off by a exploding pain in the back of his head. He collapsed to the ground, and he dimly heard Dexter's voice squawk from his Omnitrix.

"Ben! Ben, are you there? The Fusions have retreated, something is very wrong here! Respond, Agent Tennyson!"

Ben's Fusion smirked, and tapped the communicator on the Galvan technology.

"Sorry, Ben's busy right now. Try again later."

Dexter's response was cut off as the Fusion cut the connection. The last thing Ben saw before he lost consciousness was the grinning face of the doppelganger, reaching towards him.


	2. Chapter 2

"Ben?! Ben, answer me!!"

Dexter deactivated the comm. link on his wrist, muttering obscenities. Around him, the KND were gathering their wounded and carting them into the DexLabs med-evac units. Blossom and Bubbles were helping clear away debris to free civilians trapped in the rubble of several collapsed buildings. The boy genius had already sent a KND squad led by Number 4 to search for Ben at his communicator's last signal location.

Dexter knew just how dangerous the Fusions could be, and if Ben had not checked in, then something was very wrong. Dexter suspected that Fusions were responsible for Buttercup's disappearance several months before the initial invasion by Fuse. The way it had affected the sisters and the Professor, was enough to make Dexter's blood boil.

"Oi, Dexter! You there, mate?"

Dexter shook himself from his thoughts and activated his communicator.

"Dexter here. What have you found, Number Four?" There was a pause before the KND operative responded.

"Not much. Place looks like meteor crashed into it, and it stinks like you wouldn't believe. No sign of Ben, though."

Dexter ground his teeth in frustration and combed his hand through his fiery red hair. His suspicions were being confirmed, unfortunately.

"Number Four, keep looking. Report back in an hour."

"Roger that." The pre-teen replied, disconnecting the line.

Dexter rubbed his eyes tiredly with a free hand.

"Where are you, Ben?"

* * *

"_Ugh, where am I?"_

As Ben gradually struggled out of the deep slumber of unconsciousness, he cracked open his eyes and tried to get a bearing of his surroundings.

Wherever he was, it was dark, with only an ambient green glow lighting up the room. The walls were made of cold, somber-colored bedrock, hinted he was underground. There wasn't much in the room beside himself, although the stench of Fusion was so thick it was almost a green mist in the air.

Ben tried to swallow, but his throat was so dry his tongue felt like a lump of rubber in his mouth. He coughed a few times, the sensation scratching his parched throat, and pulled against his bonds that kept him shackled to the wall.

"Ah, so you're awake? Good, I hoped we could begin soon."

Ben's head snapped up at the sound of the voice, the red eyes glowing out of the gloom. Ben's Fusion stopped in front of him, their eyes level, one pair bright green, the other glowing crimson.

"Welcome to our humble abode, Ben Tennyson. I trust you're enjoying our hospitality?" The Fusion asked. The way this thing twisted his mannerisms to itself always creeped Ben out. It was almost his polar opposite. A negative Ben, to his 10.

"Oh yeah, it's a regular Four Seasons in here. Can I get some of those little pillow mints?" Ben asked sarcastically, trying to buy some time. His eyes flicked over the room, looking for anything to aid in his escape.

Nega-Ben's lips curled in a smirk.

"Afraid not. We do, however, have a lovely electro-static therapy session. Allow me." The Fusion walked out of Ben's line of sight, and Ben could hear the high-pitched crackle of energy and a hum of power through the steel plate he was strapped to. Then the lightning struck, and liquid fire lanced through his veins.

* * *

Nigel Uno was having a very bad day. Not only was one of his friends MIA, but his entire team was spread so thin across the war effort, his ability to keep the KND in the area running was pushed to the limit. When it was apparent Planet Fusion was on a collision course with the Moon Base, Number 362 had ordered Operation B.O.O.M. (Bad Outcome On Moon). If Fuse had absorbed the Moon Base, then all the Kids Next Door's technology and Intel would have been revealed. Rather then give Fuse that much of an advantage over Earth's Forces, the Moon Base's self-destruct was activated. So, since 362 was out in the field for the next few months, it was up to Number One to run things.

"I still don't get how we got stuck with stinking clean-up work." Number Two grumbled as he used the scanner in his hand (made from a Gameboy and an old camera) to check the area for traces of Fusion Matter. Number One rolled his eyes behind his glasses.

"Because, Number Two, Tennyson wouldn't just leave a battle like that. Something must have happened, and it's our job to find out what. Any Fusion Matter on the scanner?"

Number Two frowned beneath his leather pilot's hat.

"Tons of the stuff. And Tennyson's DNA, too. Weird, though…"

Number One frowned as Number Two trailed off, intent on the scanner.

"What is it, Hoagie?"

"Ben's DNA…there're two signatures. And one of them is _soaked_ in Fusion goo."

The dots connected in Number One's mind like a constellation in the sky. Tennyson disappearing, the sudden retreat by Fuse's forces, the communication jammer on Ben's comm. Only one thing made sense.

"Ben's got a Fusion."

* * *

Ben couldn't tell how much time had gone past. The shocks had made time meaningless, seconds stretching into centuries. He slumped against his cuffs, his muscles weak and twitching from the electricity.

"My friend, I _am_ sorry about the discomfort. I wouldn't have resorted to the shocks, but, let's face it, we're a tough pair. I had to, uh, _soften you up_ before the next stage of this little enterprise."

Nega-Ben stepped up until he was a few inches from Bens nose, his crimson eyes glowing malevolently. Ben mustered his energy and sneered at his doppelganger.

"Thanks for the concern, you slimy jack-ass." The Fusion's expression didn't change.

"Oh, don't worry. That was only the beginning." Nega-Ben was standing in front of a metal table littered with tools and medical supplies. Ben, exhausted as he was, managed to be curious.

"Whatcha cookin up there, Fusionstein? A better mousetrap?" Ben forced bravado into his tone, despite how his stomach was trying to claw its way up his throat. The Fusion laughed darkly. He turned, a syringe full of a dark green glowing liquid in hand.

"Not exactly, Benjamin." He walked up to Ben, tapping the needle to dislodge any air bubbles. "What I have in mind is a little more…Dr Jekyll."

Ben struggled against his bonds, but was unable to move. The Omnitrix kept out of his reach, Ben could only watch helplessly as the Fusion walked towards him, needle gleaming in the sparse light of the chamber.

"Don't worry, Ben. It won't hurt for long." Ben looked to the left for the sound of the feminine voice. Black hair, green eyes and matching outfit. He recognized her from a picture her sisters had shown him once.

"Buttercup! Thank God, get me out of here so I can kick this little puke's butt!" Ben cried, overjoyed at the appearance of an ally. Something was off, though. The Powerpuff reminded him of a Fusion, with green tinged skin and her eyes had a faint red glow. Buttercup had disappeared a few months before the Fuse Invasion, but, seeing her, instead of making him relieved, made him uneasy. The evil smirk on her face didn't help things.

"Buttercup?" The Powerpuff's grin widened.

"Yes, and don't worry Ben. It won't hurt…much." Nega-Ben approached the Omnitrix wielder, syringe ready.

"Well, Benjamin, this is it." The doppelganger said as Ben struggled with renewed vigor against his restraints, shouting in protest. Ben cried out as the needle was plunged into the vein at his wrist.

The plunger sent the green sludge shooting into his system, the infection spreading like wildfire though his blood. Ben bellowed in horror and agony as his arm convulsed with pain, his skin tingeing green. When the virus touched the Omnitrix, it began rapidly flashing red and green, sparks of energy dancing off the alien technology.

The Fusion Ben grinned as the infection spread past Ben's elbow.

"Welcome to the family, brother."


	3. Chapter 3

"What do you mean, you guys don't know where he is? How hard can it be to find the most powerful device in the universe?"

Dexter's eye twitched in annoyance as he glared at the unwelcome and _very _loud visitor to his laboratory.

" I assure you, Mr. Levin, I and the entirety of Earth's United Forces are working around the clock to bring Ben home!" Dexter replied, trying to be professional despite his rising annoyance. Ben was one of Dexter's best friends, and this former criminal had the gal to storm into his lab and _accuse_ him of apathy in the search efforts.

"Oh, that is such a load of-!" Kevin was cut of as a swirl of pink energy covered his mouth. The young lady standing behind him, who had dark red hair down to her mid back, was controlling the energy with her hand, then dismissed it with a wave.

"We know you're doing everything you can to find my cousin, Dexter, and we appreciate everyone's help finding him. " Gwen told the boy genius, stomping on Kevin's foot in the process. The Osmosian teen grimaced and swore under his breath.

Dexter nodded and looked her in the eye.

"Gwen, Ben is a dear friend of mine. You have my word, we will find him." Gwen smiled at that, as Kevin crossed his arms, a mulish expression on his face.

"I know you will. Kevin and I are going to help some of the teams search the park where he was last seen. Please, contact us if you find out anything." Gwen asked, her eyes a bit misty, but her jaw firm and determined. Dexter nodded as he gestured for Computress to open the huge blast door that was the lab's main entrance.

After they left the room, Dexter sighed and took off his glasses. Rubbing his eyes, he told Computress to prepare him a cup of coffee. There was much work to be done, and very little time.

Meanwhile, light years away, on the planet Galvin Prime…

The lab overlooked the bustling cityscape, giving a panoramic view of the most technologically advanced civilization in the galaxy. It owner and creator stood near the window, gazing across the city, deep in thought. This was none other than Azimuth, creator of the Omnitrix and the smartest being in 3 galaxies (arguable 5 galaxies). Before him, on a small display, information in half a dozen languages scrolled past, detailing the conflict between Earth and Planet Fusion. The most troubling news, however, were the reports of Ben's disappearance.

"I told you the kid wasn't a good choice for the Omnitrix, but nooo, when do you ever listen to me?" Azimuth's assistant said behind him. The Galvan sighed and shook his head.

"Myaxx, just because you don't see the value in the boy, it doesn't mean he is not worthy. In fact, it more or less _proves_ the boy is." He replied, turning to address his second-in-command.

"Well, what do you intend to do, now that the Omnitrix is likely in the hands of Fuse?" Myaxx asked the diminutive genius. He made several adjustments to a handheld device and began to walk away.

"Myaxx, summon my personal shuttle and access the specialized storage units. Have Project: Ultimate up and running, and prepare it for transport." His tone brokered no argument as a small disk levitated him off the floor.

"Set our destination for Earth and contact the Plumbers for an escort to Earth. We'll need some extra protection to escape Fuse's blockade." Myaxx, thought naturally argumentative, knew when a smart remark would get her deported) the inventor had done it before), so she nodded and began to make his request into action.

"Numbah One, we could use some help here!" Number 627 yelled into his microphone, while he and the rest of his battalion fought off a crown of Fusion monsters. A huge swarm had attacked Genius Grove and Downtown, and the squads searching for Ben had all been called back to fight.

"_Not to worry, Numbah 627, help is on the way." _Nigel Uno, the local commander replied through their headsets. "_How long can you-"_ The transmission was interrupted as Numbah 627 was knocked down by the fist of a Heavy Hunter, which barely grazed him, yet was powerful enough to knock him back several feet.

His vision blurry from sweat and dust, he turned his head back to his squad, but Terrorpins had already swarmed them. Panicking, 627 turned and sprinted, desperate to escape the Fusion Monsters. He turned a street corner, and collided with someone on the other side. The KND operative stumbled and fell onto th3 ground, then looked up at who he ran into. When he did, he sighed in sweet relief.

"General Tennyson, sir, you can't imagine how relieved I am to see you. There's an entire pack of monsters behind me!" 627 yelled, clearly still panicked. He may not have ever met Ben Tennyson before, but his signature jacket and Omnitrix were instantly recognizable.

Ben glanced over the operative's shoulder and saw the pack of beasts barreling towards them. He smirked a toothy grin as he shouldered past the child soldier.

"I've got this handled." Ben said, but his gaze did not leave the Fusions as he said this. His hand moved to the Omnitrix, and he slammed down on its faceplate.

_Big Chill!_

After the green flash faded, Ben stood in the form of a Necrofriggian, icy vapor misting from his mouth. However, instead of charging at the Fusion beasts, he turned to the KND operative at his side. Then, 627 got a good look at his eyes. Instead of the normal neon green common to all Ben's transformations, they glowed an eerie scarlet.

"Uh, General Tennyson, sir…are you okay?" 627 asked, fear creeping into his tone. Ben chuckled.

"Never better." He said confidently, then, he sent Numbah 627 reeling with a blast of arctic mist. Coughing and choking on the freezing gas, he could barely see as the sweat on his body froze, stiffening his limbs as he lost feeling in his fingers. He tried to cry out for help, but no sound escaped his frozen throat. The last thing 627 ever heard was Ben's rasp of "All Hail Fuse." As the air thickened in his lungs and he lost consciousness, the world melting to black around him.


End file.
